General Motors (GM) has reached a joint venture agreement with Penske Corporation to purchase a 50% equity stake in VM Motori S.p.A, a designer and manufacturer of diesel engines based in Cento, Italy. VM Motori is one of GM’s development partners for a new closed loop control combustion (CLCC) diesel engine.
At the Geneva Motor Show earlier this year, GM announced that it is jointly developing with VM Motori a new 184 kW (247 hp), 550 Nm (406 lb-ft), 2.9-liter V-6 turbo diesel engine scheduled to launch in the Cadillac CTS in Europe in 2009. (Earlier post.) The V-6 is the first production application of the clean combustion process called closed loop combustion control.
The high-pressure, common-rail system for the engine provides up to 2,000 bar (29,000 psi) injection pressure. The injectors are quick-firing piezo-electrically actuated, and allow up to eight injections per engine cycle. The after-treatment system includes an oxidation catalyst and a particulate filter that are close coupled to the engine to achieve future emissions standards. An electronically controlled variable geometry turbocharger generates boost pressure.
Key enablers of the CLCC system are high-speed, piezo-resistive cylinder pressure sensors that are integrated within the engine glow plugs. These specialized sensors acquire real-time data from the combustion process, enabling instantaneous fine-tuning of the fuel injection process.
GM worked with Ricardo on developing an advanced diesel engine control (ADEC) system designed to enable consistent achievement of very low emissions levels through closed loop control of the combustion process. The ADEC coordinator uses a range of sensors to measure combustion states and then establishes the optimal balance of fuel quantity and timing and air path control. (Earlier post.)
In the future, this clean combustion control technology will be introduced in other GM Powertrain diesel engines. A future version of such a CLCC system with cylinder pressure sensors will likely be an enabler of HCCI (homogeneous charge compression ignition) combustion regimes.
Diesel engines have a very important role in GM’s global advanced propulsion strategy. We are leveraging expertise and resources within our company and through technology partners to ensure we develop the world’s best powertrains.—Tom Stephens, group vice president, GM Global Powertrain and Quality
VM Motori will build the new CLCC unit at its plant in Cento, Italy, and is responsible for the mechanical aspects of the engine’s design, development and testing.
Penske Corporation, based in Bloomfield, Mich., is a transportation services company that encompasses retail automotive sales and services, truck leasing, supply chain logistics management, transportation components manufacturing, and high-performance racing.
VM Motori, founded in 1947, specializes in engine design and production for a variety of uses, including light commercial vehicles.
GM currently offers 17 diesel engine variants in 45 vehicle lines around the world. GM sells more than one million diesel engines annually, with products that offer a range of choices from the 1.3-liter four-cylinder diesel engine sold in the Opel Agila and Corsa, up to the 6.6L V-8 Duramax diesel sold in full-size vans, heavy duty pickups and medium duty trucks in the US.
GM Vice Chairman Bob Lutz recently confirmed that the company will be introducing V-6 and V-8 diesels into the North American market. (Earlier post.)